1. choose the correct simplification of the expression −5x2(4x − 6x2 − 3). 30x4 − 20x3 + 15x2 −11x4 − x3 − 8x2 −30x4 + 20x3 − 15x2 30x4 + 20x3 + 15x2 2. simplify (6x2 − 3 + 5x3) − (4x3 − 2x2 − 16). 2x3 − x2 + 21 −2x3 + x2 − 21 x3 + 8x2 + 13 −x3 − 8x2 + 13

Afarmer sells 9.5 kilograms of apples and pears at the farmer's market. 4/5 of the weight is the apples and the rest is the pears. how many kilograms of pears did she sell at the farmers market

Which of the following disjunctions is true? 4 + 4 = 16 or 6 - 5 = 11 4 · 3 = 7 or 3 - 2 = 5 8 - 5 = 13 or 7 · 2 = 12 7 - 4 = 11 or 6 + 3 = 9

Aspacecraft can attain a stable orbit 300 kilometers above earth if it reaches a velocity of 7.7 kilometers per second. the formula for a rocket's maximum velocity v in kilometers per second is vequalsminus0.0098tplusc ln upper r, where t is the firing time in seconds, c is the velocity of the exhaust in kilometers per second, and r is the ratio of the mass of the rocket filled with fuel to the mass of the rocket without fuel. find the velocity of a spacecraft whose booster rocket has a mass ratio of 20, an exhaust velocity of 2.1 km/s, and a firing time of 15 s. can the spacecraft achieve a stable orbit 300 km above earth?